Rheological properties of cement mixes: III. The effects of mixing procedures on viscometric properties of mixes containing superplasticizers

The effects of mixing procedures upon rheological properties of cement mixes with and without superplasticizing admixtures have been investigated. The results are discussed in terms of the dispersion of structures. The effects upon yielding stress, plastic viscosity and hysteresis were studied by a co-axial viscometer. In the absence of admixture, yielding stress and plastic viscosity decreased substantially with increasing intensity of mixing, which caused a breakdown of particulate aggregates. However, with admixture present, the rheological properties of already well-dispersed mixes did not change much with increasingly intense mixing.